Materials for organic electroluminescent devices

ABSTRACT

The present invention relates to compounds of the formula (1) which are suitable for use in electronic devices, in particular organic electroluminescent devices, and to electronic devices which comprise these compounds.

The present invention relates to a compound of the formula (1), to theuse of the compound in an electronic device, and to an electronic devicecomprising a compound of the formula (1). The present inventionfurthermore relates to a process for the preparation of a compound ofthe formula (1) and to a formulation comprising one or more compounds ofthe formula (1).

The development of functional compounds for use in electronic devices iscurrently the subject of intensive research. The aim is, in particular,the development of compounds with which improved properties ofelectronic devices in one or more relevant points can be achieved, suchas, for example, power efficiency and lifetime of the device as well ascolour coordinates of the emitted light.

In accordance with the present invention, the term electronic device istaken to mean, inter alia, organic integrated circuits (OICs), organicfield-effect transistors (OFETs), organic thin-film transistors (OTFTs),organic light-emitting transistors (OLETs), organic solar cells (OSCs),organic optical detectors, organic photoreceptors, organic field-quenchdevices (OFQDs), organic light-emitting electrochemical cells (OLECs),organic laser diodes (O-lasers) and organic electroluminescent devices(OLEDs).

Of particular interest is the provision of compounds for use in thelast-mentioned electronic devices called OLEDs. The general structureand the functional principle of OLEDs are known to the person skilled inthe art and are described, for example, in U.S. Pat. No. 4,539,507.

Further improvements are still necessary with respect to the performancedata of OLEDs, in particular with a view to broad commercial use, forexample in display devices or as light sources. Of particular importancein this connection are the lifetime, the efficiency and the operatingvoltage of the OLEDs and as well as the colour values achieved. Inparticular, in case of blue-emitting OLEDs, there is potential forimprovement with respect to the lifetime and the efficiency of thedevices.

An important starting point for achieving the said improvements is thechoice of the emitter compound and of the host compound employed in theelectronic device.

Blue-fluorescent emitters known from the prior art are a multiplicity ofcompounds. Arylamines containing one or more condensed aryl groups likefluorene and indenofluorene derivatives are known from the prior, forexample in accordance with WO 2008006449 or WO 2016108419.

However, there is still a need for further fluorescent emitters,especially blue-fluorescent emitters, which may be employed in OLEDs andlead to OLEDs having good properties in terms of lifetime, colouremission and efficiency.

Furthermore, it is known that an OLED may comprise different layers,which may be applied either by vapour deposition in a vacuum chamber orby processing from a solution. The processes based on vapour depositionlead to good results but such processes are complex and expensive.Therefore, there is a need for OLED materials that can be easily andreliably processed from solution. In this case, the materials shouldhave good solubility properties in the solution that comprises them.Additionally, the OLED materials that are processed from a solutionshould be able to orientate themselves in the deposited film to improvethe overall efficiency of the OLED. The term orientation means here thehorizontal orientation of the transition dipole or the horizontalmolecular orientation of the compounds, as explained in Zhao et al.,Horizontal molecular orientation in solution-processed organiclight-emitting diodes, Appl. Phys. Lett. 106063301, 2015.

The present invention is thus based on the technical object of providingcompounds which are suitable for use in electronic devices, such asOLEDs, more particularly as blue-fluorescent emitters or matrixmaterials and, which are suitable for vacuum processing or for solutionprocessing, more particularly for solution processing.

In investigations on novel compounds for use in electronic devices, ithas now been found, that compounds of formula (1) as defined below areeminently suitable for use in electronic devices. In particular, theyachieve one or more, preferably all, of the above-mentioned technicalobjects.

The invention thus relates to compounds of formula (1),

where the following applies to the symbols and indices used:

-   Ar^(S) is on each occurrence, identically or differently, an    aromatic or heteroaromatic ring system having 5 to 40 aromatic ring    atoms, which may in each case also be substituted by one or more    radicals R¹;-   Ar¹, Ar², Ar³, Ar⁴ stand on each occurrence, identically or    differently, for:    -   an aromatic or heteroaromatic ring system having 5 to 60        aromatic ring atoms, which may in each case be substituted by        one or more radicals R¹; or    -   a group Ar^(L);-   Ar^(L) stands on each occurrence, identically or differently, for a    group of formula (ArL-1),

where the dashed bond in formula (ArL-1) indicates the bonding to thestructure of formula (1);

-   X stands for CR² or X stands for C, if it is bonded to Ar⁵, Ar⁶, R³    or to an adjacent fluorene-type derivative unit;-   Y stands on each occurrence, identically or differently, for —BR⁰—,    —C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —C(R⁰)₂—O—, —C(R⁰)₂—S—, —R⁰C═CR⁰—,    —R⁰C═N—, —Si(R⁰)₂—, —Si(R⁰)₂—Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—,    —C(═C(R⁰)₂)—, —O—, —S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and    —P((═O)R⁰)—;-   Ar⁵, Ar⁶ stand on each occurrence, identically or differently, for    an aryl or heteroaryl group having 6 to 18 aromatic ring atoms,    which may in each case be substituted by one or more radicals R³;-   G is, when n is 1, a group of formula (G-1),

-   -   where the dashed bonds indicate the bonding to the group        —NAr³Ar⁴ and —NAr¹Ar²;

-   G is, when n is 0, a group of formula (G-2),

-   -   where the dashed bond indicates the bonding to the group        —NAr³Ar⁴;

-   Ar⁷ stands on each occurrence, identically or differently, for an    aryl or heteroaryl group having 6 to 18 aromatic ring atoms, which    may in each case be substituted by one or more radicals R⁴, wherein    at least one of the group Ar⁷ in formulae (G-1) and (G-2) has 10 or    more aromatic ring atoms;

-   Ar⁸ stands on each occurrence, identically or differently, for an    aryl or heteroaryl group having 6 to 18 aromatic ring atoms, which    may in each case be substituted by one or more radicals R⁴ or one or    more groups Ar^(L);

-   E is identically or differently on each occurrence, selected from    —BR^(E)—, —C(R^(E))₂—, —C(R^(E))₂—C(R^(E))₂—, —C(R^(E))₂—O—,    —C(R^(E))₂—S—, —R^(E)═CR^(E), —R^(E)C═N—, Si(R^(E))₂,    —Si(R^(E))₂—Si(R^(E))₂—, —C(═O)—, —C(═NR^(E))—, —C(═C(R^(E))₂)—,    —O—, —S—, —S(═O)—, —SO₂—, —N(R^(E)), —P(R^(E))— and —P((═O)R^(E))—;    or E is a group of formula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1) or (G-2); andwhere two groups E may be in a cis- or trans-position relative to eachother;

-   E⁰ is identically or differently on each occurrence, selected from    the group consisting of a single bond, —BR⁴—, —C(R⁴)₂—,    —C(R⁴)₂—C(R⁴)₂—, —C(R⁴)₂—O—, —C(R⁴)₂—S—, —R⁴C═CR⁴—, —R⁴C═N—,    Si(R⁴)₂, —Si(R⁴)₂—Si(R⁴)₂—, —C(═O)—, —C(═NR⁴)—, —C(═C(R⁴)₂)—, —O—,    —S—, —S(═O)—, —SO₂—, —N(R⁴)—, —P(R⁴)— and —P((═O)R⁴)—;-   R^(E) stands on each occurrence, identically or differently, for:    -   H, D, F, Cl, Br, I, a straight-chain alkyl having 1 to 40 C        atoms or branched or a cyclic alkyl group having 3 to 40 C        atoms, each of which may be substituted by one or more radicals        R⁵, where in each case one or more non-adjacent CH₂ groups may        be replaced by R⁵C═CR⁵, C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O,        C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, S or CONR⁵ and where one or        more H atoms may be replaced by D, F, Cl, Br, I or CN, an        aromatic or heteroaromatic ring systems having 5 to 60 aromatic        ring atoms, which may in each case be substituted by one or more        radicals R⁵, where two adjacent substituents R^(E) may form a        mono- or polycyclic, aliphatic ring system or aromatic ring        system, which may be substituted by one or more radicals R⁵; or    -   a group Ar^(L);-   R⁰, R¹, R², R³, R⁴ stand on each occurrence, identically or    differently, for:    -   a group selected from H, D, F, C, Br, I, CHO, CN, N(Ar)₂,        C(═O)Ar, P(═O)(Ar)₂, S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁵)₃, B(OR⁵)₂,        OSO₂R⁵, a straight-chain alkyl, alkoxy or thioalkyl groups        having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or        thioalkyl groups having 3 to 40 C atoms, each of which may be        substituted by one or more radicals R⁵, where in each case one        or more non-adjacent CH₂ groups may be replaced by R⁵C═CR⁵, C≡C,        Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O, C═S, C═Se, P(═O)(R⁵), SO, SO₂,        O, S or CONR⁵ and where one or more H atoms may be replaced by        D, F, C, Br, I, CN or NO₂, an aromatic or heteroaromatic ring        systems having 5 to 60 aromatic ring atoms, which may in each        case be substituted by one or more radicals R⁵, or an aryloxy        groups having 5 to 40 aromatic ring atoms, which may be        substituted by one or more radicals R⁵; or    -   a group Ar^(L)-    where two adjacent substituents R⁰, two adjacent substituents R¹,    two adjacent substituents R², two adjacent substituents R³ and/or    two adjacent substituents R⁴, may form a mono- or polycyclic,    aliphatic ring system or aromatic ring system, which may be    substituted by one or more radicals R⁵;-   R⁵ stands on each occurrence, identically or differently, for H, D,    F, Cl, Br, I, CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂, S(═O)Ar,    S(═O)₂Ar, NO₂, Si(R⁶)₃, B(OR)₂, OSO₂R⁶, a straight-chain alkyl,    alkoxy or thioalkyl groups having 1 to 40 C atoms or branched or    cyclic alkyl, alkoxy or thioalkyl groups having 3 to 40 C atoms,    each of which may be substituted by one or more radicals R⁶, where    in each case one or more non-adjacent CH₂ groups may be replaced by    R⁶C═CR⁶, C≡C, Si(R⁶)₂, Ge(R⁶)₂, Sn(R⁶)₂, C═O, C═S, C═Se, P(═O)(R⁶),    SO, SO₂, O, S or CONR⁶ and where one or more H atoms may be replaced    by D, F, Cl, Br, I, CN or NO₂, an aromatic or heteroaromatic ring    systems having 5 to 60 aromatic ring atoms, which may in each case    be substituted by one or more radicals R⁶, or an aryloxy group    having 5 to 60 aromatic ring atoms, which may be substituted by one    or more radicals R⁶, where two adjacent substituents R⁵ may form a    mono- or polycyclic, aliphatic ring system or aromatic ring system,    which may be substituted by one or more radicals R⁶;-   Ar is an aromatic or heteroaromatic ring system having 5 to 24    aromatic ring atoms, which may in each case also be substituted by    one or more radicals R⁶;-   R⁶ stands on each occurrence, identically or differently, for H, D,    F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl groups    having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or    thioalkyl groups having 3 to 20 C atoms, where in each case one or    more non-adjacent CH₂ groups may be replaced by SO, SO₂, O, S and    where one or more H atoms may be replaced by D, F, Cl, Br or I, or    an aromatic or heteroaromatic ring system having 5 to 24 C atoms;-   n is equal to 0 or 1;-   i is equal to 0, 1 or 2;-   q, r are on each occurrence, identically or differently, an integer    selected from 1 to 10;-   p, s, t are on each occurrence, identically or differently, an    integer selected from 0 to 10; and    where the compounds of formula (1) comprise at least one group Ar¹,    Ar², Ar³, Ar⁴, R^(E), R⁰, R¹, R², R³ or R⁴, which stands for a group    Ar^(L).

Preferably, the compounds of formula (1) comprise at least one groupAr¹, Ar², Ar³ or Ar⁴, which stands for a group Ar^(L).

Adjacent substituents in the sense of the present invention aresubstituents which are bonded to atoms which are linked directly to oneanother or which are bonded to the same atom.

Furthermore, the following definitions of chemical groups apply for thepurposes of the present application:

An aryl group in the sense of this invention contains 6 to 60 aromaticring atoms, preferably 6 to 40 aromatic ring atoms, more preferably 6 to20 aromatic ring atoms; a heteroaryl group in the sense of thisinvention contains 5 to 60 aromatic ring atoms, preferably 5 to 40aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, atleast one of which is a heteroatom. The heteroatoms are preferablyselected from N, O and S. This represents the basic definition. If otherpreferences are indicated in the description of the present invention,for example with respect to the number of aromatic ring atoms or theheteroatoms present, these apply.

An aryl group or heteroaryl group here is taken to mean either a simplearomatic ring, i.e. benzene, or a simple heteroaromatic ring, forexample pyridine, pyrimidine or thiophene, or a condensed (annellated)aromatic or heteroaromatic polycycle, for example naphthalene,phenanthrene, quinoline or carbazole. A condensed (annellated) aromaticor heteroaromatic polycycle in the sense of the present applicationconsists of two or more simple aromatic or heteroaromatic ringscondensed with one another.

An aryl or heteroaryl group, which may in each case be substituted bythe above-mentioned radicals and which may be linked to the aromatic orheteroaromatic ring system via any desired positions, is taken to mean,in particular, groups derived from benzene, naphthalene, anthracene,phenanthrene, pyrene, dihydropyrene, chrysene, perylene, fluoranthene,benzanthracene, benzophenanthrene, tetracene, pentacene, benzopyrene,furan, benzofuran, isobenzofuran, dibenzofuran, thiophene,benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole,isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine,phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline,benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole,imidazole, benzimidazole, naphthimidazole, phenanthrimidazole,pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole,benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole,1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine,pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine,naphthyridine, azacarbazole, benzocarboline, phenanthroline,1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3-oxadiazole,1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole,1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine,1,2,4-triazine, 1,2,3-triazine, tetrazole, 1,2,4,5-tetrazine,1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine, pteridine, indolizine andbenzothiadiazole.

An aryloxy group in accordance with the definition of the presentinvention is taken to mean an aryl group, as defined above, which isbonded via an oxygen atom. An analogous definition applies toheteroaryloxy groups.

An aromatic ring system in the sense of this invention contains 6 to 60C atoms in the ring system, preferably 6 to 40 C atoms, more preferably6 to 20 C atoms. A heteroaromatic ring system in the sense of thisinvention contains 5 to 60 aromatic ring atoms, preferably 5 to 40aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, atleast one of which is a heteroatom. The heteroatoms are preferablyselected from N, O and/or S. An aromatic or heteroaromatic ring systemin the sense of this invention is intended to be taken to mean a systemwhich does not necessarily contain only aryl or heteroaryl groups, butinstead in which, in addition, a plurality of aryl or heteroaryl groupsmay be connected by a non-aromatic unit (preferably less than 10% of theatoms other than H), such as, for example, an sp³-hybridised C, Si, N orO atom, an sp²-hybridised C or N atom or an sp-hybridised C atom. Thus,for example, systems such as 9,9′-spirobifluorene, 9,9′-diarylfluorene,triarylamine, diaryl ether, stilbene, etc., are also intended to betaken to be aromatic ring systems in the sense of this invention, as aresystems in which two or more aryl groups are connected, for example, bya linear or cyclic alkyl, alkenyl or alkynyl group or by a silyl group.Furthermore, systems in which two or more aryl or heteroaryl groups arelinked to one another via single bonds are also taken to be aromatic orheteroaromatic ring systems in the sense of this invention, such as, forexample, systems such as biphenyl, terphenyl or diphenyltriazine.

An aromatic or heteroaromatic ring system having 5-60 aromatic ringatoms, which may in each case also be substituted by radicals as definedabove and which may be linked to the aromatic or heteroaromatic groupvia any desired positions, is taken to mean, in particular, groupsderived from benzene, naphthalene, anthracene, benzanthracene,phenanthrene, benzophenanthrene, pyrene, chrysene, perylene,fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl,biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene,spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene,cis- or trans-indenofluorene, truxene, isotruxene, spirotruxene,spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran,thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole,indole, isoindole, carbazole, indolocarbazole, indenocarbazole,pyridine, quinoline, isoquinoline, acridine, phenanthridine,benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline,phenothiazine, phenoxazine, pyrazole, indazole, imidazole,benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole,pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole,naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole,1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine,benzopyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene,2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene,4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine,phenothiazine, fluorubin, naphthyridine, azacarbazole, benzocarboline,phenanthroline, 1,2,3-triazole, 1,2,4-triazole, benzotriazole,1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole,1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole,1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine,tetrazole, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine,purine, pteridine, indolizine and benzothiadiazole, or combinations ofthese groups.

For the purposes of the present invention, a straight-chain alkyl grouphaving 1 to 40 C atoms or a branched or cyclic alkyl group having 3 to40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, inwhich, in addition, individual H atoms or CH₂ groups may be substitutedby the groups mentioned above under the definition of the radicals, ispreferably taken to mean the radicals methyl, ethyl, n-propyl, i-propyl,n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl,cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl,cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl,pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl,pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl,octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl oroctynyl. An alkoxy or thioalkyl group having 1 to 40 C atoms ispreferably taken to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy,i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s-pentoxy,2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy,n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy,2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio,i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio,n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio,cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio,trifluoromethylthio, pentafluoroethylthio, 2,2,2-trifluoroethylthio,ethenylthio, propenylthio, butenylthio, pentenylthio, cyclopentenylthio,hexenylthio, cyclohexenylthio, heptenylthio, cycloheptenylthio,octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio,pentynylthio, hexynylthio, heptynylthio or octynylthio.

The formulation that two or more radicals may form a ring with oneanother is, for the purposes of the present application, intended to betaken to mean, inter alia, that the two radicals are linked to oneanother by a chemical bond. This is illustrated by the followingschemes:

Furthermore, however, the above-mentioned formulation is also intendedto be taken to mean that, in the case where one of the two radicalsrepresents hydrogen, the second radical is bonded at the position towhich the hydrogen atom was bonded, with formation of a ring. This isillustrated by the following scheme:

In accordance with a preferred embodiment, the groups Ar, Ar², Ar³ andAr⁴ stand on each occurrence, identically or differently, for Ar^(L), orfor an aromatic or heteroaromatic ring system having 5 to 40, preferably5 to 30, more preferably 5 to 18 aromatic ring atoms, which may in eachcase be substituted by one or more radicals R. More preferably, thegroups Ar, Ar², Ar³ and Ar⁴ stand on each occurrence, identically ordifferently, for Ar^(L), or for benzene, biphenyl, terphenyl,quaterphenyl, naphthalene, anthracene, phenanthrene, pyrene, fluorene,dibenzofuran, dibenzothiophene or carbazole or 9-Phenylcarbazole; whichmay in each case be substituted by one or more radicals R¹.

In accordance with a preferred embodiment, the compound of formula (1)bears at least one group R⁰, R¹, R², R³, R⁴ or R^(E), which stands for astraight-chain alkyl group having 1 to 40, preferably 1 to 20, morepreferably 1 to 10 C atoms or branched or a cyclic alkyl group having 3to 40, preferably 3 to 20, more preferably 3 to 10 C atoms, each ofwhich may be substituted by one or more radicals R⁶.

The group Ar^(S) is preferably, identically or differently on eachoccurrence, selected from aromatic or heteroaromatic ring systems having6 to 18 aromatic ring atoms, which may in each case also be substitutedby one or more radicals R¹. More preferably, the group Ar^(S) is,identically or differently on each occurrence, selected from benzene,biphenyl, naphthalene, fluorene, dibenzofuran, dibenzothiophene orcarbazole, each of which may be substituted by one or more radicals R¹.Particularly preferably, the group Ar^(S) is, identically or differentlyon each occurrence, selected from benzene or biphenyl, each of which maybe substituted by one or more radicals R¹.

In accordance with a preferred embodiment of the invention, the index iis equal to 0. In this case, the corresponding group Ar^(S) is absentand the groups adjacent to Ar^(S) are directly bonded with one another.

In accordance with a preferred embodiment, the compounds of formula (1)are selected from the compounds of formulae (2) to (10),

where the symbols and indices have the same meaning as above.

Preferably, the index Y stands on each occurrence, identically ordifferently, for —C(R⁰)₂—, —Si(R⁰)₂—, —C(═O)—, —O—, —S—, or —N(R⁰)—.Very preferably, the index Y stands on each occurrence, identically ordifferently, for —C(R⁰)₂—, —Si(R⁰)₂—, —O— or —S—.

Particularly preferably, the index Y stands for —C(R⁰)₂— and the groupAr^(L) is a group of formula (ArL-2),

Preferably, the groups Ar⁵ and Ar⁶ are selected, identically ordifferently, from the group consisting of the groups of formulae (Ar5-1)to (Ar5-26),

where the dashed bonds indicate the bonding to the adjacent groupsdepicted in formula (1), where the groups of formulae (Ar5-1) to(Ar5-26) may be substituted at each free position by a group R³, whichhas the same meaning as in claim 1 and where E¹ is selected from—B(R⁰—), —C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—,—C═(C(R⁰))₂—, —O—, —S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and—P((═O)R⁰)—, where the substituent R⁰ has the same meaning as above.

Among groups of formulae (Ar5-1) to (Ar5-26), groups of formulae(Ar5-1), (Ar5-2), (Ar5-3), (Ar5-18), (Ar5-19), (Ar5-20), (Ar5-21),(Ar5-22) and (Ar5-23) are preferred.

Very preferably, the groups Ar⁵ and Ar⁶ are selected, identically ordifferently, from the group consisting of the groups of formulae(Ar5-27) to (Ar5-37),

where the dashed bonds indicate the bonding to the adjacent groupsdepicted in formula (1) and the groups of formulae (Ar5-27) to (Ar5-37)may be substituted at each free position by a group R³, which has thesame meaning as above and where E¹ in formulae (Ar5-30) to (Ar5-32) hasthe same meaning as above.

Among groups of formulae (Ar5-27) to (Ar5-37), groups of formulae(Ar5-27) to (Ar5-32) are preferred.

In accordance with a preferred embodiment, the group Ar^(L) is selectedfrom the groups of one of the formulae (ArL-3) to (ArL-8),

where the dashed bond indicates the bonding to the structure of formula(1) and where the symbols and indices X, R⁰, R³, Ar⁶, E¹, r, p, q and thave the same meaning as above.

In accordance with a very preferred embodiment, the group Ar^(L) isselected from the groups of one of the formulae (ArL-3-1) to (ArL-8-1),

where the dashed bond indicates the bonding to the structure of formula(1) and where the symbols and indices X, R⁰, R³, Ar⁶, E¹, r, p, q and thave the same meaning as above.

In accordance with a particularly preferred embodiment, the group Ar^(L)is selected from the groups of one of the formulae (ArL-3-2) to(ArL-8-2),

where the dashed bond indicates the bonding to the structure of formula(1) and where the symbols and indices R⁰, R³, Ar⁶, F¹, r, p, q and thave the same meaning as above.

Preferably, the group Ar⁶ stands on each occurrence, identically ordifferently, for an aryl group having 6 to 14 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R³. Morepreferably, Ar⁶ 15 stands on each occurrence, identically ordifferently, for abenzene, naphthalene, biphenyl or fluorene group,which may in each case be substituted by one or more radicals R³. When pis 0, the corresponding group Ar⁶ is absent and the groups adjacent toAr⁶ are directly bonded with one another.

Preferably, the group R⁰ stands on each occurrence, identically ordifferently, for H, D, F, a straight-chain alkyl having 1 to 20,preferably 1 to 10 C atoms or branched or a cyclic alkyl group having 3to 20, preferably 3 to 10 C atoms, each of which may be substituted byone or more radicals R, where in each case one or more non-adjacent CH₂groups may be replaced by R⁵C═CR⁵, or S, and where one or more H atomsmay be replaced by D or F, an aromatic or heteroaromatic ring systemshaving 5 to 40, preferably 5 to 30, more preferably 5 to 18 aromaticring atoms, which may in each case be substituted by one or moreradicals R⁵, where two adjacent substituents R⁰ may form a mono- orpolycyclic, aliphatic ring system or aromatic ring system, which may besubstituted by one or more radicals R⁵.

Preferably, t is equal to 1.

Preferably, q and r are on each occurrence, identically or differently,an integer selected from 1 to 5, more preferably from 1 to 2.

Preferably, p is an integer selected from 0 to 5, more preferably from 0to 2.

In accordance with a very particularly preferred embodiment, the groupAr^(L) is selected from the groups of one of the formulae (ArL-3-3) to(ArL-8-3),

where the dashed bond indicates the bonding to the structure of formula(1) and where the symbols and indices R⁰, R³ and E¹ have the samemeaning as above.

According to the invention, the group G is a group of formula (G-1) or(G-2). In the groups of formulae (G-1) and (G-2), it is preferred that sis 0, 1 or 2. More preferably, s is 0 or 1.

When s is equal to 0 the group G of formula (G-1) corresponds to a groupof formula (G-1-s0),

where the dashed bonds indicate the bonding to the group —NAr³Ar⁴ and—NAr¹Ar²;and the group G of formula (G-2) corresponds to a group of formula(G-2-s0),

where the dashed bond indicates the bonding to the group —NAr³Ar⁴;

In the groups of formulae (G-1) and (G-2), it is preferred that thegroup Ar⁷ stands on each occurrence, identically or differently, forbenzene, naphthalene, anthracene, phenanthrene, pyrene, dibenzofuran,dibenzothiophene, carbazole, pyridine, quinoline, isoquinoline,acridine, phenanthridine, benzoquinoline, phenothiazine or phenoxazine,each of which may be substituted by one or more radicals R⁴ or by one ormore groups Ar^(L), wherein at least one of the group Ar⁷ in formula(G-1) stands for naphthalene, anthracene, phenanthrene, pyrene,dibenzofuran, dibenzothiophene, carbazole, quinoline, isoquinoline,acridine, phenanthridine, benzoquinoline, phenothiazine or phenoxazine,each of which may be substituted by one or more radicals R⁴ or by one ormore groups Ar^(L).

More preferably, the group Ar⁷ stands on each occurrence, identically ordifferently, for benzene, naphthalene, anthracene, phenanthrene,dibenzofuran, dibenzothiophene, phenothiazine or phenoxazine, each ofwhich may be substituted by one or more radicals R⁴ or by one or moregroups Ar^(L), wherein at least one of the group Ar⁷ in formula (G-1)stands for naphthalene, anthracene, phenanthrene, dibenzofuran,dibenzothiophene, phenothiazine or phenoxazine, each of which may besubstituted by one or more radicals R⁴ or by one or more groups Ar^(L).

Preferably, the group Ar⁸ stands on each occurrence, identically ordifferently, for an aryl or heteroaryl group having 6 aromatic ringatoms, which may in each case be substituted by one or more radicals R⁴or by one or more groups Ar^(L). More preferably, the group Ar⁸ standson each occurrence, identically or differently, for benzene, which maybe substituted by one or more radicals R⁴ or by one or more groupsAr^(L),

It is preferred that the group of formula (G-1) is selected from thegroups of formulae (G-1-1) to (G-1-23),

where

-   -   the dashed bonds indicate the bonding to the adjacent groups as        depicted in formula (1);    -   the groups of formulae (G-1-1) to (G-1-23) may be substituted by        one or more radicals R⁴ or one or more groups Ar^(L) at any free        positions;    -   E² stands, on each occurrence, identically or differently, for        —C(R^(E))₂—, —O— or —S—; and    -   the symbols E, R^(E) have the same meaning as above.

It is more preferred that the group of formula (G-1) is selected fromthe groups of formulae (G-1-24) to (G-1-46),

where

-   -   the dashed bonds indicate the bonding to the adjacent groups as        depicted in formula (1);    -   the groups of formulae (G-1-21) to (G-1-46) may be substituted        by one or more radicals R⁴ or one or more groups Ar^(L) at any        free positions;    -   E² stands, on each occurrence, identically or differently, for        —C(R^(E))₂—, —O— or —S—; and    -   the symbols E, R^(E) have the same meaning as above.

It is preferred that the group of formula (G-2) is selected from thegroup consisting of the groups of formulae (G-2-1) to (G-2-40),

where

-   -   the dashed bond indicates the bonding to the adjacent group as        depicted in formula (1);    -   the groups of formulae (G-2-1) to (G-2-40) may be substituted by        one or more radicals R⁴ or Ar^(L) at any free positions;    -   E² stands, on each occurrence, identically or differently, for        —C(R^(E))₂—, —O— or —S—; and    -   the symbols E and R^(E) have the same meaning as above.

It is more preferred that the group of formula (G-2) is selected fromthe group consisting of the groups of formulae (G-2-41) to (G-2-80),

where

-   -   the dashed bond indicates the bonding to the adjacent group as        depicted in formula (1);    -   the groups of formulae (G-2-40) to (G-2-80) may be substituted        by one or more radicals R⁴ or Ar^(L) at any free positions;    -   E² stands, on each occurrence, identically or differently, for        —C(R^(E))₂—, —O— or —S—; and    -   the symbol R^(E) has the same meaning as above.

Preferably, the group E is, identically or differently, on eachoccurrence, selected from —C(R^(E))₂—, —Si(R^(E))₂—, and a group offormula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1), (G-2), (G-1-1) to (G-1-46), or (G-2-1) to (G-2-80).

The group of formula (E-1) is preferably selected from the groups offormulae (E-2), (E-3) or (E-4),

where the symbol * in formulae (E-2) to (E-4) indicates thecorresponding group E in formula (G-1), (G-2), (G-1-1) to (G-1-46), or(G-2-1) to (G-2-80) and where R⁴ has the same meaning as above.

Preferably, the group R^(E) stands on each occurrence, identically ordifferently, for Ar^(L) or for H, D, F, a straight-chain alkyl having 1to 20, preferably 1 to 10 C atoms or branched or a cyclic alkyl grouphaving 3 to 20, preferably 3 to 10 C atoms, each of which may besubstituted by one or more radicals R⁵, where in each case one or morenon-adjacent CH₂ groups may be replaced by R⁵C═CR⁵, O or S, and whereone or more H atoms may be replaced by D or F, an aromatic orheteroaromatic ring systems having 5 to 40, preferably 5 to 30, morepreferably 5 to 18 aromatic ring atoms, which may in each case besubstituted by one or more radicals R⁵, where two adjacent substituentsR^(E) may form a mono- or polycyclic, aliphatic ring system or aromaticring system, which may be substituted by one or more radicals R⁵.

Preferably, the group E⁰ is identically or differently on eachoccurrence, selected from the group consisting of a single bond,—C(R⁵)₂—, —Si(R⁵)₂—, —O—, —S— and —N(R⁵)—. More preferably, the group E⁰is identically or differently on each occurrence, selected from thegroup consisting of a single bond, —C(R⁵)₂—, —O— and —S—.

In accordance with a preferred embodiment of the invention, thecompounds of formula (1) are selected from formulae (11) to (160),

where the benzene rings explicitly disclosed in formulae (11) to (160)may be substituted by a group R⁴ at any free position and where thesymbols Ar^(L), Ar¹, Ar², Ar³, Ar⁴, R^(E), E⁰, E² have the same meaningas above.

In accordance with a preferred embodiment, R¹, R², R³, R⁴ stand on eachoccurrence, identically or differently, for H, D, F, CN, N(Ar)₂,Si(R⁵)₃, a straight-chain alkyl or alkoxy groups having 1 to 20,preferably 1 to 10 C atoms or branched or a cyclic alkyl or alkoxygroups having 3 to 20, preferably 3 to 10 C atoms, each of which may besubstituted by one or more radicals R⁵, where in each case one or morenon-adjacent CH₂ groups may be replaced by R⁵C═CR⁵, Si(R⁵)₂, C═O, SO,SO₂, O or S and where one or more H atoms may be replaced by D or F, anaromatic or heteroaromatic ring systems having 5 to 40, preferably 5 to30, more preferably 5 to 18 aromatic ring atoms, which may in each casebe substituted by one or more radicals R⁵, where two adjacentsubstituents R, two adjacent substituents R¹, two adjacent substituentsR², two adjacent substituents R³ and/or two adjacent substituents R⁴,may form a mono- or polycyclic, aliphatic ring system or aromatic ringsystem, which may be substituted by one or more radicals R⁵.

Preferably, R⁵ stands on each occurrence, identically or differently,for H, D, F, Cl, Br, I, CN, a straight-chain alkyl group having 1 to 10C atoms or branched or cyclic alkyl group having 3 to 10 C atoms, eachof which may be substituted by one or more radicals R⁶, an aromatic orheteroaromatic ring systems having 5 to 18 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁶.

Preferably, Ar is an aromatic or heteroaromatic ring system having 5 to18 aromatic ring atoms, which may in each case also be substituted byone or more radicals R⁶;

Preferably, R⁶ stands on each occurrence, identically or differently,for H, D, F, Cl, Br, I, CN, a straight-chain alkyl group having 1 to 10C atoms or branched or cyclic alkyl group having 3 to 10 C atoms, or anaromatic or heteroaromatic ring system having 5 to 18 C atoms.

The following compounds are examples of compounds of the formula (1):

The compounds according to the invention can be prepared by synthesissteps known to the person skilled in the art, such as, for example,bromination, Suzuki coupling, Ullmann coupling, Hartwig-Buchwaldcoupling, etc. Examples of suitable synthesis processes are depicted ingeneral terms in Schemes 1 to 4 below.

where in Schemes 1 to 4, the groups G and Ar^(L) have the same meaningas above, the group Ar is an aromatic or heteroaromatic group system,and the group X is a halogen atom (like Br, Cl, I) or another leavinggroup.

The compounds of formula (1) may be synthesized as described above:

-   -   At least one diarylamine group comprising at least one group        Ar^(L) as defined above is bonded via a C—N coupling to a        condensed aryl group G as defined above, substituted with at        least one halogen or another leaving group (for example via a        Hartwig-Buchwald coupling); or    -   At least one group Ar^(L), which is substituted with at least        one halogen or another leaving group, is bonded via a C—C        coupling to a condensed aryl group G as defined above, which is        substituted with at least one halogen or another leaving group        (for example via a Suzuki coupling).

For the processing of the compounds according to the invention from theliquid phase, for example by spin coating or by printing processes,formulations of the compounds according to the invention are necessary.These formulations can be, for example, solutions, dispersions oremulsions. It may be preferred to use mixtures of two or more solventsfor this purpose.

Suitable and preferred solvents are, for example, toluene, anisole, o-,m- or p-xylene, methyl benzoate, mesitylene, tetralin, veratrol, THF,methyl-THF, THP, chlorobenzene, dioxane, phenoxytoluene, in particular3-phenoxytoluene, (−)-fenchone, 1,2,3,5-tetramethylbenzene,1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole,2-phenoxyethanol, 2-pyrrolidinone, 3-methylanisole, 4-methylanisole,3,4-dimethylanisole, 3,5-dimethylanisole, acetophenone, α-terpineol,benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone,cyclohexylbenzene, decalin, dodecylbenzene, ethyl benzoate, indane,methyl benzoate, NMP, p-cymene, phenetole, 1,4-diisopropylbenzene,dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycolbutyl methyl ether, diethylene glycol dibutyl ether, triethylene glycoldimethyl ether, diethylene glycol-monobutyl ether, tripropylene glycoldimethyl ether, tetraethylene glycol dimethyl ether,2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene,octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane or mixtures of thesesolvents.

The present invention therefore furthermore relates to a formulationcomprising a compound according to the invention and at least onefurther compound. The further compound may be, for example, a solvent,in particular one of the above-mentioned solvents or a mixture of thesesolvents. However, the further compound may also be at least one furtherorganic or inorganic compound which is likewise employed in theelectronic device, for example an emitting compound, in particular afluorescent dopant, and/or a further matrix material. Suitable emittingcompounds and further matrix materials are indicated below in connectionwith the organic electroluminescent device. This further compound mayalso be polymeric.

The compounds and mixtures according to the invention are suitable foruse in an electronic device. An electronic device here is taken to meana device which comprises at least one layer which comprises at least oneorganic compound. However, the component here may also compriseinorganic materials or also layers built up entirely from inorganicmaterials.

The present invention therefore furthermore relates to the use of thecompounds or mixtures according to the invention in an electronicdevice, in particular in an organic electroluminescent device.

The present invention again furthermore relates to an electronic devicecomprising at least one of the compounds or mixtures according to theinvention mentioned above. The preferences stated above for the compoundalso apply to the electronic devices.

The electronic device is preferably selected from the group consistingof organic electroluminescent devices (OLEDs, PLEDs), organic integratedcircuits (O-ICs), organic field-effect transistors (O-FETs), organicthin-film transistors (O-TFTs), organic light-emitting transistors(O-LETs), organic solar cells (O-SCs), organic dye-sensitised solarcells, organic optical detectors, organic photoreceptors, organicfield-quench devices (O-FQDs), light-emitting electrochemical cells(LECs), organic laser diodes (O-lasers) and “organic plasmon emittingdevices” (D. M. Koller et al., Nature Photonics 2008, 1-4), preferablyorganic electroluminescent devices (OLEDs, PLEDs), in particularphosphorescent OLEDs.

The organic electroluminescent device comprises a cathode, an anode andat least one emitting layer. Apart from these layers, it may alsocomprise further layers, for example in each case one or morehole-injection layers, hole-transport layers, hole-blocking layers,electron-transport layers, electron-injection layers, exciton-blockinglayers, electron-blocking layers and/or charge-generation layers. It islikewise possible for interlayers, which have, for example, anexciton-blocking function, to be introduced between two emitting layers.However, it should be pointed out that each of these layers does notnecessarily have to be present. The organic electroluminescent devicehere may comprise one emitting layer or a plurality of emitting layers.If a plurality of emission layers are present, these preferably have intotal a plurality of emission maxima between 380 nm and 750 nm,resulting overall in white emission, i.e. various emitting compoundswhich are able to fluoresce or phosphoresce are used in the emittinglayers. Particular preference is given to systems having three emittinglayers, where the three layers exhibit blue, green and orange or redemission (for the basic structure see, for example, WO 2005/011013).These can be fluorescent or phosphorescent emission layers or hybridsystems, in which fluorescent and phosphorescent emission layers arecombined with one another.

The compound according to the invention in accordance with theembodiments indicated above can be employed in various layers, dependingon the precise structure and on the substitution. Preference is given toan organic electroluminescent device comprising a compound of theformula (1) or in accordance with the preferred embodiments asfluorescent emitters, emitters showing TADF (Thermally Activated DelayedFluorescence), matrix material for fluorescent emitters. Particularlypreferred is an organic electroluminescent device comprising a compoundof the formula (1) or in accordance with the preferred embodiments asfluorescent emitters, more particularly blue-emitting fluorescentcompound.

The compounds of formula (1) can also be employed in anelectron-transport layer and/or in an electron-blocking orexciton-blocking layer and/or in a hole-transport layer, depending onthe precise substitution. The preferred embodiments indicated above alsoapply to the use of the materials in organic electronic devices.

The compound according to the invention is particularly suitable for useas blue-emitting emitter compound. The electronic device concerned maycomprise a single emitting layer comprising the compound according tothe invention or it may comprise two or more emitting layers. Thefurther emitting layers here may comprise one or more compoundsaccording to the invention or alternatively other compounds.

If the compound according to the invention is employed as a fluorescentemitting compound in an emitting layer, it is preferably employed incombination with one or more matrix materials. A matrix material here istaken to mean a material which is present in the emitting layer,preferably as the principal component, and which does not emit light onoperation of the device.

The proportion of the emitting compound in the mixture of the emittinglayer is between 0.1 and 50.0%, preferably between 0.5 and 20.0%,particularly preferably between 1.0 and 10.0%. Correspondingly, theproportion of the matrix material or matrix materials is between 50.0and 99.9%, preferably between 80.0 and 99.5%, particularly preferablybetween 90.0 and 99.0%.

The specifications of the proportions in % are, for the purposes of thepresent application, taken to mean % by vol. if the compounds areapplied from the gas phase and % by weight if the compounds are appliedfrom solution.

Preferred matrix materials for use in combination with fluorescentemitting compounds are selected from the classes of the oligoarylenes(for example 2,2′,7,7′-tetraphenylspirobifluorene in accordance with EP676461 or dinaphthylanthracene), in particular the oligoarylenescontaining condensed aromatic groups, the oligoarylenevinylenes (forexample DPVBi or spiro-DPVBi in accordance with EP 676461), thepolypodal metal complexes (for example in accordance with WO2004/081017), the hole-conducting compounds (for example in accordancewith WO 2004/058911), the electron-conducting compounds, in particularketones, phosphine oxides, sulfoxides, etc. (for example in accordancewith WO 2005/084081 and WO 2005/084082), the atropisomers (for examplein accordance with WO 2006/048268), the boronic acid derivatives (forexample in accordance with WO 2006/117052) or the benzanthracenes (forexample in accordance with WO 2008/145239). Particularly preferredmatrix materials are selected from the classes of the oligoarylenes,comprising naphthalene, anthracene, benzanthracene and/or pyrene oratropisomers of these compounds, the oligoarylenevinylenes, the ketones,the phosphine oxides and the sulfoxides. Very particularly preferredmatrix materials are selected from the classes of the oligoarylenes,comprising anthracene, benzanthracene, benzophenanthrene and/or pyreneor atropisomers of these compounds. An oligoarylene in the sense of thisinvention is intended to be taken to mean a compound in which at leastthree aryl or arylene groups are bonded to one another.

Particularly preferred matrix materials for use in combination with thecompounds of the formula (1) in the emitting layer are depicted in thefollowing table.

If the compound according to the invention is employed as a fluorescentemitting compound in an emitting layer, it may be employed incombination with one or more other fluorescent emitting compounds.

Preferred fluorescent emitters, besides the compounds according to theinvention, are selected from the class of the arylamines. An arylaminein the sense of this invention is taken to mean a compound whichcontains three substituted or unsubstituted aromatic or heteroaromaticring systems bonded directly to the nitrogen. At least one of thesearomatic or heteroaromatic ring systems is preferably a condensed ringsystem, particularly preferably having at least 14 aromatic ring atoms.Preferred examples thereof are aromatic anthracenamines, aromaticanthracenediamines, aromatic pyrenamines, aromatic pyrenediamines,aromatic chrysenamines or aromatic chrysenediamines. An aromaticanthracenamine is taken to mean a compound in which one diarylaminogroup is bonded directly to an anthracene group, preferably in the9-position. An aromatic anthracene-diamine is taken to mean a compoundin which two diarylamino groups are bonded directly to an anthracenegroup, preferably in the 9,10-position. Aromatic pyrenamines,pyrenediamines, chrysenamines and chrysenediamines are definedanalogously thereto, where the diarylamino groups are preferably bondedto the pyrene in the 1-position or in the 1,6-position. Furtherpreferred emitters are indenofluorenamines or indenofluorene-diamines,for example in accordance with WO 2006/108497 or WO 2006/122630,benzoindenofluorenamines or benzoindenofluorenediamines, for example inaccordance with WO 2008/006449, and dibenzoindenofluorenamines ordibenzoindenofluorenediamines, for example in accordance with WO2007/140847, and the indenofluorene derivatives containing condensedaryl groups which are disclosed in WO 2010/012328. Still furtherpreferred emitters are benzanthracene derivatives as disclosed in WO2015/158409, anthracene derivatives as disclosed in WO 2017/036573,fluorene dimers like in WO 2016/150544 or phenoxazine derivatives asdisclosed in WO 2017/028940 and WO 2017/028941. Preference is likewisegiven to the pyrenarylamines disclosed in WO 2012/048780 and WO2013/185871. Preference is likewise given to thebenzoindenofluorenamines disclosed in WO 2014/037077, thebenzofluorenamines disclosed in WO 2014/106522 and the indenofluorenesdisclosed in WO 2014/111269 or WO 2017/036574.

Examples of preferred fluorescent emitting compounds, besides thecompounds according to the invention, which can be used in combinationwith the compounds of the invention in an emitting layer or which can beused in another emitting layer of the same device are depicted in thefollowing table:

The compounds according to the invention can also be employed in otherlayers, for example as hole-transport materials in a hole-injection orhole-transport layer or electron-blocking layer or as matrix materialsin an emitting layer, preferably as matrix materials for phosphorescentemitters.

If the compound of the formula (I) is employed as hole-transportmaterial in a hole-transport layer, a hole-injection layer or anelectron-blocking layer, the compound can be employed as pure material,i.e. in a proportion of 100%, in the hole-transport layer, or it can beemployed in combination with one or more further compounds. According toa preferred embodiment, the organic layer comprising the compound of theformula (I) then additionally comprises one or more p-dopants. Thep-dopants employed in accordance with the present invention arepreferably organic electron-acceptor compounds which are able to oxidiseone or more of the other compounds of the mixture.

Particularly preferred embodiments of p-dopants are the compoundsdisclosed in WO 2011/073149, EP 1968131, EP 2276085, EP 2213662,EP1722602, EP 2045848, DE102007031220, U.S. Pat. Nos. 8,044,390,8,057,712, WO 2009/003455, WO 2010/094378, WO 2011/120709, US2010/0096600 and WO 2012/095143.

If the compound of the formula (1) is employed as matrix material incombination with a phosphorescent emitter in an emitting layer, thephosphorescent emitter is preferably selected from the classes andembodiments of phosphorescent emitters indicated below. Furthermore, oneor more further matrix materials are preferably present in the emittinglayer in this case.

So-called mixed-matrix systems of this type preferably comprise two orthree different matrix materials, particularly preferably two differentmatrix materials. It is preferred here for one of the two materials tobe a material having hole-transporting properties and for the othermaterial to be a material having electron-transporting properties. Thecompound of the formula (1) is preferably the material havinghole-transporting properties.

However, the desired electron-transporting and hole-transportingproperties of the mixed-matrix components may also be combined mainly orcompletely in a single mixed-matrix component, where the furthermixed-matrix component or components satisfy other functions. The twodifferent matrix materials may be present here in a ratio of 1:50 to1:1, preferably 1:20 to 1:1, particularly preferably 1:10 to 1:1 andvery particularly preferably 1:4 to 1:1. Mixed-matrix systems arepreferably employed in phosphorescent organic electroluminescentdevices. Further details on mixed-matrix systems are contained, interalia, in the application WO 2010/108579.

Particularly suitable matrix materials which can be used as matrixcomponents of a mixed-matrix system in combination with the compoundsaccording to the invention are selected from the preferred matrixmaterials for phosphorescent emitters indicated below or the preferredmatrix materials for fluorescent emitters, depending on what type ofemitter compound is employed in the mixed-matrix system.

Generally preferred classes of material for use as correspondingfunctional materials in the organic electroluminescent devices accordingto the invention are indicated below.

Suitable phosphorescent emitters are, in particular, compounds whichemit light, preferably in the visible region, on suitable excitation andin addition contain at least one atom having an atomic number greaterthan 20, preferably greater than 38 and less than 84, particularlypreferably greater than 56 and less than 80. The phosphorescent emittersused are preferably compounds which contain copper, molybdenum,tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium,platinum, silver, gold or europium, in particular compounds whichcontain iridium, platinum or copper.

For the purposes of the present invention, all luminescent iridium,platinum or copper complexes are regarded as phosphorescent compounds.

Examples of the phosphorescent emitters described above are revealed bythe applications WO 2000/70655, WO 2001/41512, WO 2002/02714, WO2002/15645, EP 1191613, EP 1191612, EP 1191614, WO 2005/033244, WO2005/019373 and US 2005/0258742. In general, all phosphorescentcomplexes as used in accordance with the prior art for phosphorescentOLEDs and as are known to the person skilled in the art in the area oforganic electroluminescent devices are suitable for use in the devicesaccording to the invention. The person skilled in the art will also beable to employ further phosphorescent complexes without inventive stepin combination with the compounds according to the invention in OLEDs.Preferred matrix materials for phosphorescent emitters are aromaticketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones,for example in accordance with WO 2004/013080, WO 2004/093207, WO2006/005627 or WO 2010/006680, triarylamines, carbazole derivatives, forexample CBP (N,N-biscarbazolylbiphenyl) or the carbazole derivativesdisclosed in WO 2005/039246, US 2005/0069729, JP 2004/288381, EP 1205527or WO 2008/086851, indolocarbazole derivatives, for example inaccordance with WO 2007/063754 or WO 2008/056746, indenocarbazolederivatives, for example in accordance with WO 2010/136109, WO2011/000455 or WO 2013/041176, azacarbazole derivatives, for example inaccordance with EP 1617710, EP 1617711, EP 1731584, JP 2005/347160,bipolar matrix materials, for example in accordance with WO 2007/137725,silanes, for example in accordance with WO 2005/111172, azaboroles orboronic esters, for example in accordance with WO 2006/117052, triazinederivatives, for example in accordance with WO 2010/015306, WO2007/063754 or WO 2008/056746, zinc complexes, for example in accordancewith EP 652273 or WO 2009/062578, diazasilole or tetraazasilolederivatives, for example in accordance with WO 2010/054729,diazaphosphole derivatives, for example in accordance with WO2010/054730, bridged carbazole derivatives, for example in accordancewith US 2009/0136779, WO 2010/050778, WO 2011/042107, WO 2011/088877 orWO 2012/143080, triphenylene derivatives, for example in accordance withWO 2012/048781, or lactams, for example in accordance with WO2011/116865 or WO 2011/137951.

Besides the compounds according to the invention, suitablecharge-transport materials, as can be used in the hole-injection orhole-transport layer or electron-blocking layer or in theelectron-transport layer of the electronic device according to theinvention, are, for example, the compounds disclosed in Y. Shirota etal., Chem. Rev. 2007, 107(4), 953-1010, or other materials as areemployed in these layers in accordance with the prior art.

Materials which can be used for the electron-transport layer are allmaterials as are used in accordance with the prior art aselectron-transport materials in the electron-transport layer.Particularly suitable are aluminium complexes, for example Alq₃,zirconium complexes, for example Zrq4, lithium complexes, for exampleLiq, benzimidazole derivatives, triazine derivatives, pyrimidinederivatives, pyridine derivatives, pyrazine derivatives, quinoxalinederivatives, quinoline derivatives, oxadiazole derivatives, aromaticketones, lactams, boranes, diazaphosphole derivatives and phosphineoxide derivatives. Furthermore, suitable materials are derivatives ofthe above-mentioned compounds, as disclosed in JP 2000/053957, WO2003/060956, WO 2004/028217, WO 2004/080975 and WO 2010/072300.

Preferred hole-transport materials which can be used in ahole-transport, hole-injection or electron-blocking layer in theelectroluminescent device according to the invention areindenofluorenamine derivatives (for example in accordance with WO06/122630 or WO 06/100896), the amine derivatives disclosed in EP1661888, hexaazatriphenylene derivatives (for example in accordance withWO 01/049806), amine derivatives containing condensed aromatic rings(for example in accordance with U.S. Pat. No. 5,061,569), the aminederivatives disclosed in WO 95/09147, monobenzoindenofluorenamines (forexample in accordance with WO 08/006449), dibenzoindenofluorenamines(for example in accordance with WO 07/140847), spirobifluorenamines (forexample in accordance with WO 2012/034627 or WO 2013/120577),fluorenamines (for example in accordance with the as yet unpublishedapplications EP 12005369.9, EP 12005370.7 and EP 12005371.5),spirodibenzopyranamines (for example in accordance with WO 2013/083216)and dihydroacridine derivatives (for example in accordance with WO2012/150001). The compounds according to the invention can also be usedas hole-transport materials.

The cathode of the organic electroluminescent device preferablycomprises metals having a low work function, metal alloys ormultilayered structures comprising various metals, such as, for example,alkaline-earth metals, alkali metals, main-group metals or lanthanoids(for example Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Also suitable arealloys comprising an alkali metal or alkaline-earth metal and silver,for example an alloy comprising magnesium and silver. In the case ofmultilayered structures, further metals which have a relatively highwork function, such as, for example, Ag or Al, can also be used inaddition to the said metals, in which case combinations of the metals,such as, for example, Ca/Ag, Mg/Ag or Ag/Ag, are generally used. It mayalso be preferred to introduce a thin interlayer of a material having ahigh dielectric constant between a metallic cathode and the organicsemiconductor. Suitable for this purpose are, for example, alkali metalfluorides or alkaline-earth metal fluorides, but also the correspondingoxides or carbonates (for example LiF, Li₂O, BaF₂, MgO, NaF, CsF,Cs₂CO₃, etc.). Furthermore, lithium quinolinate (LiQ) can be used forthis purpose. The layer thickness of this layer is preferably between0.5 and 5 nm.

The anode preferably comprises materials having a high work function.The anode preferably has a work function of greater than 4.5 eV vs.vacuum. Suitable for this purpose are on the one hand metals having ahigh redox potential, such as, for example, Ag, Pt or Au. On the otherhand, metal/metal oxide electrodes (for example Al/Ni/NiOx, Al/PtOx) mayalso be preferred. For some applications, at least one of the electrodesmust be transparent or partially transparent in order to facilitateeither irradiation of the organic material (organic solar cells) or thecoupling-out of light (OLEDs, O-lasers). Preferred anode materials hereare conductive mixed metal oxides. Particular preference is given toindium tin oxide (ITO) or indium zinc oxide (IZO). Preference isfurthermore given to conductive, doped organic materials, in particularconductive doped polymers.

The device is appropriately (depending on the application) structured,provided with contacts and finally sealed, since the lifetime of thedevices according to the invention is shortened in the presence of waterand/or air.

In a preferred embodiment, the organic electroluminescent deviceaccording to the invention is characterised in that one or more layersare coated by means of a sublimation process, in which the materials areapplied by vapour deposition in vacuum sublimation units at an initialpressure of less than 10⁻⁵ mbar, preferably less than 10⁻⁶ mbar.However, it is also possible here for the initial pressure to be evenlower, for example less than 10⁻⁷ mbar.

Preference is likewise given to an organic electroluminescent device,characterised in that one or more layers are coated by means of the OVPD(organic vapour phase deposition) process or with the aid of carrier-gassublimation, in which the materials are applied at a pressure of between10⁻⁵ mbar and 1 bar. A special case of this process is the OVJP (organicvapour jet printing) process, in which the materials are applieddirectly through a nozzle and are thus structured (for example M. S.Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

Preference is furthermore given to an organic electroluminescent device,characterised in that one or more layers are produced from solution,such as, for example, by spin coating, or by means of any desiredprinting process, such as, for example, screen printing, flexographicprinting, nozzle printing or offset printing, but particularlypreferably LITI (light induced thermal imaging, thermal transferprinting) or ink-jet printing. Soluble compounds of the formula (I) arenecessary for this purpose. High solubility can be achieved throughsuitable substitution of the compounds.

Also possible are hybrid processes, in which, for example, one or morelayers are applied from solution and one or more further layers areapplied by vapour deposition. Thus, it is possible, for example, toapply the emitting layer from solution and to apply theelectron-transport layer by vapour deposition.

These processes are generally known to the person skilled in the art andcan be applied by him without inventive step to organicelectroluminescent devices comprising the compounds according to theinvention.

In accordance with the invention, the electronic devices comprising oneor more compounds according to the invention can be employed indisplays, as light sources in lighting applications and as light sourcesin medical and/or cosmetic applications (for example light therapy).

The invention will now be explained in greater detail by the followingexamples, without wishing to restrict it thereby.

A) SYNTHESIS EXAMPLES A-1) Indenofluorene and Benzofluorene Derivatives

Synthesis of Compound Int1.1

30 g (97.5 mmol) 2-Bromo-7-Chloro-9,9-dimethyl-9H-fluorene (see JP2003277305 A), 25.5 g (107.3 mmol) (9,9-dimethylfluoren-2-yl)boronicacid 90 g (390 mmol), 0.9 g (4 mmol) palladium(II)acetate and 3.6 g(11.7 mmol) tri(o-tolyl)-phosphine are dissolved in 1 liter of atoluene, dioxane, water mixture (1:1:1) and stirred at reflux overnight.After cooling down to room temperature 200 mL toluene are added and theorganic phase is separated and washed with water (2×200 ml) the combinedorganic phases are concentrated under reduced pressure. The residue ispurified by recrystallization from toluene/heptane.

Yield: 39.1 g (93 mmol; 96%)

Following compounds can be synthesized in an analogous manner in similaryields:

Com- Starting Starting pound material A material B Product Int1.2

Int1.3

Int1.4

Synthesis of EG1

40 g (95 mmol) Int1.1, 38.6 g (152 mmol) bis-(pinacolato)-diboron, 4.2 g(5.7 mmol) trans-dichloro(tricyclohexylphosphine)palladium(II) and 28 g(285 mmol) potassium acetate are dissolved in 400 ml dioxane and stirredfor 16 h at reflux. The reaction mixture is allowed to cool to roomtemperature and 400 ml toluene are added. The organic phase isseparated, washed with water (2×200 mL) and filtered through Celite. Thesolution is concentrated to dryness under reduced pressure. The residueis purified by recrystallization from toluene/heptane.

Yield: 36 g (70 mmol; 74%)

Following compounds can be synthesized in an analogous manner in similaryields:

Compound Starting material Product EG2 Int1.2

EG3 Int1.3

Synthesis of Int2.4

5.5 g (17.8 mmol) 2-Bromo-5-iodo-1,3-dimethylbenzene, 6.5 g (12.7 mmol)EG1, 366 mg (0.3 mmol) tetrakis(triphenylphosphin)-palladium(0) and 2.7g (13 mmol) sodium carbonate are dissolved in 200 ml toluene, ethanoland water (2:1:1) and stirred for 16 hours at 90° C. After cooling downto room temperature 100 ml toluene are added, the organic phase isseparated and washed with water (2×50 ml). The organic phase isconcentrated to dryness under reduced pressure. The residue is purifiedby recrystallization from toluene/heptane.

Yield: 6.2 g (11 mmol; 86%)

The following compounds can be synthesized in an analogous manner insimilar yields:

Starting Starting Compound material A material B Product Int2.5 EG2 CAS106-93-8

Int2.6 EG2

Int2.7 CAS 1679-18-1 Int2.4

Synthesis of EG4 to EG6:

Compounds EG3 to EG5 can be synthesized in an analogous manner to EG1 insimilar yields:

Starting Compound material Product EG4 Int2.8

EG5 Int2.7

EG6 Int2.5

Synthesis of the Amine (EA.1):

12.2 g (37.3 mmol)bis-(4-bromo-phenyl)-amine, 55.5 g (78.4 mmol) EG.2,37.8 g (164.2 mmol) potassium phosphate monohydrate and 1.2 g (1.5 mmol)XPhos Pd Gen 3 (GAS 1445085-55-1) are added to 600 mL THF/water (2:1)and stirred at 65° C. After 16 h the mixture is cooled to roomtemperature diluted with toluene and H2O. The organic phase iscollected, the aqueous phase is extracted further with toluene. Thecombined organics are washed with brine, collected, dried with Na₂SO₄,filtered and concentrated. The resulting residue is deposited in 1 LEtOH and stirred vigorously until free flowing precipitate is formed.The precipitate is collected by filtration and washing with EtOH. Thematerial is taken up in DCM and filtered through SiO₂. The filtrate isconcentrated to dryness.

Yield: 44.7 g (33.6 mmol; 90%)

The following compounds EA.2 to EA.6 can be synthesized in analogousmanner and similar yields:

Comp. SM1 SM2 Product EA.2 EG1

EA.3 EG1

EA.4 EG4

EA.5 EG3

EA.6 EG.2

Compounds A1.1

10.0 g (7.4 mmol) EA.1, 3.6 g (8.2 mmol) Core 1, 0.74 ml (0.74 mmol)tri-tertbutylphosphine (1M in toluene), 2.14 g (22.3 mmol)sodium-tert-butylate and 83.5 mg (0.37 mmol)palladium(II)diacetate wereadded to 250 ml toluene and stirred at 100° C. After 16 h the reactionmixture was allowed to room temperature, diluted with toluene and H2O.The organic phase was collected, the aqueous phase extracted furtherwith toluene. The combined organic phases were washed with brine,collected, dried with Na2SO4, filtered and concentrated. The resultingresidue was dissolved in toluene and filtered through silica andconcentrated. The precipitate was further purified by recrystallisationfrom toluene/heptane and tempering (250° C., <10⁻⁴ mbar).

Yield: 4.4 g (2.6 mmol; 35%)

The following compounds can be synthesized in analogous manner. For thesynthesis of compounds D stoichiometry of the amine was doubled.

Comp. SM1 Core Product A1.2 EA.2 1

A1.3 EA.3 1

A2.1 EA.4 2

A2.2 EA.1 2

A3.1 EA.1 4

A4.1 EA.1 3

Compound EA.7

Compound E can be done in analogous manner like compound C, using 1 eq.of EA.6 and one equivalent of CAS1134188-18-3

Compounds A4.2, A2.3, A3.2

Compound A4.2 can be synthesized in analogous manner to compound A1.1.For the synthesis of compounds A2.3 and A3.2 stoichiometry of the aminewas doubled.

Compound SM1 SM2 A2.3 EA.7 Core 2

A3.2 EA.7 Core 3

B) Dibenzofurane Derivatives

Synthesis Compound B:

In a 250-ml round-bottom flask reactor, 2-bromobiphenyl (8.4 g, 0.036mol) and tetrahydrofuran (110 ml) are cooled down to −78° C. At the sametemperature, n-butyl lithium (19.3 ml, 0.031 mol) is dropwise added tothe reaction solution and stirred for 2 hours. Thereafter, compound A(13.5 g, 0.026 mol) is added little by little to the reaction solutionand stirred at room temperature. After full conversion of compound A thereaction is stopped with H2O (50 ml), extraction is conducted with ethylacetate and water. The organic layer are separated, concentrated in avacuum and recrystallized in acetonitrile to afford the intermediate asa solid. This is again dissolved in acetic acid (120 ml), and sulfuricacid (2 ml) and stirred for 5 hours under reflux. After full conversionof the intermediate the reaction mixture is then cooled to roomtemperature and filtered. Further purification is done byrecrystalisation from toluene/heptane. (15.1 g, 0.023 88%)

Following compounds can be obtained in analogous manner and similaryields:

Compound Starting material A Starting material B Product B.1

B.2

B.3

B.4

B.5

B.6

B.7

Synthesis of Compound C.1

In a 250-ml round-bottom flask, a mixture of B.1 (6.2 g, 0.009 mol),bis(4-tert-butylphenyl)amine (6.0 g, 0.021 mol), palladium (II) acetate(0.08 g, 0.4 mmol), sodium tert-butoxide (3.4 g, 0.035 mol),tri-tertbutylphosphine (0.07 g, 0.4 mmol), and toluene (60 ml) isstirred for 2 hrs under reflux. After completion of the reaction, thereaction mixture is cooled to room temperature and then extracted withdichloromethane and water. The organic phase is separated, dried overmagnesium sulfate, and concentrated in a vacuum. The concentrate isfurther purified by column chromatography and recrystallized indichloromethane and acetone to yield the compound C1 as a solid (3.6 g,37%).

Starting material A Starting material B Product C.2

C.3

C.4

C.5

C.6

C.7

Synthesis of Compounds D

The Synthesis of compound D.1 to D.7 is analog to the synthesis of EA.1.In case there is only one chloride attached to the starting material Aonly 1.1 equivalents of the boronate are used:

Educt A B Product D.1

EG5

D.2

EG5

D.3

EG5

D.4

EG5

D.5

EG6

D.6

EG5

D.7

EG5

Synthesis of Compounds E and G:

The Synthesis of compounds E and G is analog to the synthesis of C.1:

Educt A Educt B Product G.1

EA.1

G.2

EA.5

G.3

EA.4

G.4

EA.1

G.5

EA.1

E.1

EA.3

E.2

EA.2

E.3

EA.1

E.4

EA.1

B) Fabrication of OLEDs

The production of solution-based OLEDs has already been described manytimes in the literature, for example in WO2004/037887 and WO2010/097155. The process is adapted to the circumstances described below(layer-thickness variation, materials).

The inventive material combinations are used in the following layersequence:

-   -   substrate,    -   ITO (50 nm),    -   hole-injection layer HIL (20 nm),    -   hole-transport layer (HTL) (20 nm),    -   emission layer (EML) (30 nm),    -   hole-blocking layer (HBL) (10 nm)    -   electron-transport layer (ETL) (40 nm),    -   cathode (Al) (100 nm).

Glass plates coated with structured ITO (indium tin oxide) in athickness of 50 nm serve as substrate. The hole-injection layer isapplied via spin coating in an inert atmosphere. For this, ahole-transporting, crosslinkable polymer and a p-dopant salt aredissolved in toluene. Corresponding materials are for example describedin WO 2016/107668, WO 2013/081052 and EP 2325190. The solids content ofsuch solutions is about 6 mg/ml if, as here, the layer thicknesses of 20nm is to be achieved by means of spin coating. The layers are applied byspin coating in an inert-gas atmosphere, and dried by heating at 200° C.for 30 minutes on a heating plate. The hole-transport and the emissionlayer are applied to these coated glass plates.

The hole-transport layer is the polymer of the structure shown in Table3, which was synthesised in accordance with WO2013156130. The polymer isdissolved in toluene, so that the solution typically has a solid contentof approx. 5 g/l if, as here, the layer thickness of 20 nm which istypical for a device is to be achieved by means of spin coating. Thelayers are applied by spin coating in an inert-gas atmosphere, in thepresent case argon, and dried by heating at 220° C. for 30 min.

The emission layer is composed of the matrix material (host material) H1and the emitting dopant (emitter) D1. Both material are present in theemission layer in a proportion of 92% by weight H1 and 8% by weight D1.The mixture for the emission layer is dissolved in toluene. The solidscontent of such solutions is about 9 mg/ml if, as here, the layerthickness of 30 nm which is typical for a device is to be achieved bymeans of spin coating. The layers are applied by spin coating in aninert-gas atmosphere, and dried by heating at 170° C. for 10 minutes.

The materials used in the present case are shown in Table 3.

TABLE 3 Structures of the materials used

HTL1

H1

V-D1

V-D2

V-D3

D1

D2

D3

D4

D5

The materials for the hole-blocking layer and electron-transport layerare likewise applied by thermal vapour deposition in a vacuum chamberand are shown in Table 4. The hole-blocking layer consists of ETM1. Theelectron-transport layer consists of the two materials ETM1 and ETM2,which are mixed with one another in a proportion by volume of 50% eachby co-evaporation.

TABLE 4 HBL and ETL materials used

ETM1

ETM2

The cathode is formed by the thermal evaporation of an aluminium layerwith a thickness of 100 nm.

The OLEDs are characterised by standard methods. For this purpose, theelectroluminescence spectra are recorded, the current efficiency(measured in cd/A) and the external quantum efficiency (EQE, measured inpercent) as a function of the luminous density assuming Lambert emissioncharacteristics are calculated from current/voltage/luminous densitycharacteristic lines (IUL characteristic lines). The electroluminescencespectra are recorded at a luminous density of 1000 cd/m², and the CIE1931 x and y colour coordinates are calculated from this data. The termEQE @1000 cd/m² denotes the external quantum efficiency at an operatingluminous density of 1000 cd/m².

The properties of the various OLEDs are summarised in Table 5. ExampleV01 is the comparative example, whereas E1 to E4 show properties ofOLEDs containing materials of the present invention.

TABLE 5 Properties of the OLEDs EQE EML EML [%] at Example host dopant1000 cd/m² CIE x/y V01 H1 V-D1 2.9 0.14/0.12 V02 H1 V-D2 3.5 0.14/0.14V03 H1 V-D3 3.3 0.15/0.17 E01 H1 D1 4.0 0.14/0.13 E02 H1 D2 4.20.14/0.14 E03 H1 D3 4.9 0.14/0.14 E04 H1 D4 4.7 0.14/0.11 E05 H1 D5 5.20.15/0.17

Table 5 shows, that use of materials according to the present inventiongives rise to improvements over the prior art when used as fluorescentblue emitters, in particular with respect to efficiency.

1. Compound of the formula (1),

where the following applies to the symbols and indices used: Ar^(S) ison each occurrence, identically or differently, an aromatic orheteroaromatic ring system having 5 to 40 aromatic ring atoms, which mayin each case also be substituted by one or more radicals R¹; Ar¹, Ar²,Ar³, Ar⁴ stand on each occurrence, identically or differently, for: anaromatic or heteroaromatic ring system having 5 to 60 aromatic ringatoms, which may in each case be substituted by one or more radicals R¹;or a group Ar^(L); Ar^(L) stands on each occurrence, identically ordifferently, for a group of formula (ArL-1),

where the dashed bond in formula (ArL-1) indicates the bonding to thestructure of formula (1); X stands for CR² or X stands for C, if it isbonded to Ar⁵, Ar⁶, R³ or to an adjacent fluorene-type derivative unit;Y stands on each occurrence, identically or differently, for —BR⁰—,—C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —C(R⁰)₂—O—, —C(R⁰)₂—S—, —R⁰C═CR⁰—, —R⁰C═N—,—Si(R⁰)₂—, —Si(R⁰)₂—Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—, —C(═C(R⁰)₂)—, —O—,—S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and —P((═O)R⁰)—; Ar⁵, Ar⁶ stand oneach occurrence, identically or differently, for an aryl or heteroarylgroup having 6 to 18 aromatic ring atoms, which may in each case besubstituted by one or more radicals R³; G is, when n is 1, a group offormula (G-1),

where the dashed bonds indicate the bonding to the group —NAr³Ar⁴ and—NAr¹Ar²; G is, when n is 0, a group of formula (G-2),

where the dashed bond indicates the bonding to the group —NAr³Ar⁴; Ar⁷stands on each occurrence, identically or differently, for an aryl orheteroaryl group having 6 to 18 aromatic ring atoms, which may in eachcase be substituted by one or more radicals R⁴, wherein at least one ofthe group Ar⁷ in formulae (G-1) and (G-2) has 10 or more aromatic ringatoms; Ar⁸ stands on each occurrence, identically or differently, for anaryl or heteroaryl group having 6 to 18 aromatic ring atoms, which mayin each case be substituted by one or more radicals R⁴ or one or moregroups Ar^(L); E is identically or differently on each occurrence,selected from —BR^(E)—, —C(R^(E))₂—, —C(R^(E))₂—C(R^(E))₂—,—C(R^(E))₂—O—, —C(R^(E))₂—S—, —R^(E)C═CR^(E)—, —R^(E)C═N—, Si(R^(E))₂,—Si(R^(E))₂—Si(R^(E))₂—, —C(═O)—, —C(═NR^(E))—, —C(═C(R^(E))₂)—, —O—,—S—, —S(═O)—, —SO₂—, —N(R^(E))—, —P(R^(E))— and —P((═O)R^(E))—; or E isa group of formula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1) or (G-2); and where two groups E may be in a cis- ortrans-position relative to each other; E⁰ is identically or differentlyon each occurrence, selected from the group consisting of a single bond,—BR⁴—, —C(R⁴)₂—, —C(R⁴)₂—C(R⁴)₂—, —C(R⁴)₂—O—, —C(R⁴)₂—S—, —R⁴C═CR⁴—,—R⁴C═N—, Si(R⁴)₂, —Si(R⁴)₂—Si(R⁴)₂—, —C(═O)—, —C(═NR⁴)—, —C(═C(R⁴)₂)—,—O—, —S—, —S(═O)—, —SO₂—, —N(R⁴)—, —P(R⁴)— and —P((═O)R⁴)—; R^(E) standson each occurrence, identically or differently, for: H, D, F, Cl, Br, I,a straight-chain alkyl having 1 to 40 C atoms or branched or a cyclicalkyl group having 3 to 40 C atoms, each of which may be substituted byone or more radicals R⁵, where in each case one or more non-adjacent CH₂groups may be replaced by R⁵C═CR⁵, C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O,C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, S or CONR⁵ and where one or more Hatoms may be replaced by D, F, Cl, Br, I or CN, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁵, where twoadjacent substituents R^(E) may form a mono- or polycyclic, aliphaticring system or aromatic ring system, which may be substituted by one ormore radicals R⁵; or R^(E) stands for a group Ar^(L); R⁰, R¹, R², R³, R⁴stand on each occurrence, identically or differently, for: a groupselected from H, D, F, Cl, Br, I, CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂,S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁵)₃, B(OR⁵)₂, OSO₂R⁵, a straight-chainalkyl, alkoxy or thioalkyl groups having 1 to 40 C atoms or branched ora cyclic alkyl, alkoxy or thioalkyl groups having 3 to 40 C atoms, eachof which may be substituted by one or more radicals R⁵, where in eachcase one or more non-adjacent CH₂ groups may be replaced by R⁵C═CR⁵,C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O, C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, Sor CONR⁵ and where one or more H atoms may be replaced by D, F, Cl, Br,I, CN or NO₂, an aromatic or heteroaromatic ring systems having 5 to 60aromatic ring atoms, which may in each case be substituted by one ormore radicals R⁵, or an aryloxy groups having 5 to 40 aromatic ringatoms, which may be substituted by one or more radicals R⁵; or R⁰, R¹,R², R³ and/or R⁴ stands for a group Ar^(L); where two adjacentsubstituents R⁰, two adjacent substituents R¹, two adjacent substituentsR², two adjacent substituents R³ and/or two adjacent substituents R⁴,may form a mono- or polycyclic, aliphatic ring system or aromatic ringsystem, which may be substituted by one or more radicals R⁵; R⁵ standson each occurrence, identically or differently, for H, D, F, Cl, Br, I,CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂, S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁶)₃,B(OR⁶)₂, OSO₂R⁶, a straight-chain alkyl, alkoxy or thioalkyl groupshaving 1 to 40 C atoms or branched or cyclic alkyl, alkoxy or thioalkylgroups having 3 to 40 C atoms, each of which may be substituted by oneor more radicals R⁶, where in each case one or more non-adjacent CH₂groups may be replaced by R⁶C═CR⁶, C≡C, Si(R⁶)₂, Ge(R⁶)₂, Sn(R⁶)₂, C═O,C═S, C═Se, P(═O)(R⁶), SO, SO₂, O, S or CONR⁶ and where one or more Hatoms may be replaced by D, F, Cl, Br, I, CN or NO₂, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁶, or anaryloxy group having 5 to 60 aromatic ring atoms, which may besubstituted by one or more radicals R⁶, where two adjacent substituentsR⁵ may form a mono- or polycyclic, aliphatic ring system or aromaticring system, which may be substituted by one or more radicals R⁶; Ar isan aromatic or heteroaromatic ring system having 5 to 24 aromatic ringatoms, which may in each case also be substituted by one or moreradicals R⁶; R⁶ stands on each occurrence, identically or differently,for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkylgroups having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy orthioalkyl groups having 3 to 20 C atoms, where in each case one or morenon-adjacent CH₂ groups may be replaced by SO, SO₂, O, S and where oneor more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic orheteroaromatic ring system having 5 to 24 C atoms; n is equal to 0 or 1;i is equal to 0, 1 or 2; q, r are on each occurrence, identically ordifferently, an integer selected from 1 to 10; p, s, t are on eachoccurrence, identically or differently, an integer selected from 0 to10; and where the compounds of formula (1) comprise at least one groupAr¹, Ar², Ar³, Ar⁴, R^(E), R⁰, R¹, R², R³ or R⁴, which stands for agroup Ar^(L).
 2. Compound according to claim 1, wherein the compound offormula (1) bears at least one group R⁰, R¹, R², R³, R⁴ or R^(E), whichstands for a straight-chain alkyl group having 1 to 40 C atoms or abranched or a cyclic alkyl group having 3 to 40 C atoms, each of whichmay be substituted by one or more radicals R⁶.
 3. Compound according toclaim 1, selected from compounds of formulae (2) to (10),

where the symbols and indices have the same meaning as in claim
 1. 4.Compound according to claim 1, wherein the group Ar^(L) is a group offormula (ArL-2),

where the symbols an indices have the same meaning as in claim
 1. 5.Compound according to claim 1, wherein Ar⁵ and Ar⁶ are selected,identically or differently, from the group consisting of the groups offormulae (Ar5-1) to (Ar5-26),

where the dashed bonds indicate the bonding to the adjacent groupsdepicted in formula (1), where the groups of formulae (Ar5-1) to(Ar5-26) may be substituted at each free position by a group R³, whichhas the same meaning as in claim 1 and where E¹ is selected from—B(R⁰—), —C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—,—C═(C(R⁰))₂—, —O—, —S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and—P((═O)R⁰)—, where the substituent R⁰ has the same meaning as inclaim
 1. 6. Compound according to claim 1, wherein Ar⁵ and Ar⁶ areselected, identically or differently, from the group consisting of thegroups of formulae (Ar5-27) to (Ar5-37),

where the dashed bonds indicate the bonding to the adjacent groupsdepicted in formula (1) and the groups of formulae (Ar5-26) to (Ar5-32)may be substituted at each free position by a group R³, which has thesame meaning as in claim 1 and where the substituent the group E¹ informulae (Ar5-30) to (Ar5-32) has the same meaning as in claim
 1. 7.Compound according to claim 1, wherein the group Ar^(L) is selected fromthe groups of formulae (ArL-3) to (ArL-8),

where the dashed bond indicates the bonding to the structure of formula(1) and where the symbols and indices X, R⁰, R³, Ar⁶, E¹, r, p, q and thave the same meaning as in claim
 1. 8. Compound according to claim 1,wherein r and q are on each occurrence, identically or differently,equal to 1, 2, 3, 4 or
 5. 9. Compound according to claim 1 wherein Ar⁶stands on each occurrence, identically or differently, for an aryl grouphaving 6 to 14 aromatic ring atoms, which may in each case besubstituted by one or more radicals R³.
 10. Compound according to claim1, wherein Ar⁶ stands on each occurrence, identically or differently,for a benzene, naphthalene, biphenyl or fluorene group, which may ineach case be substituted by one or more radicals R³.
 11. Compoundaccording to claim 1, wherein the group R⁰ stands on each occurrence,identically or differently, for H, D, F, a straight-chain alkyl having 1to 20 C atoms or branched or a cyclic alkyl group having 3 to 20 Catoms, each of which may be substituted by one or more radicals R⁵,where in each case one or more non-adjacent CH₂ groups may be replacedby R⁵C═CR⁵, O or S, and where one or more H atoms may be replaced by Dor F, an aromatic or heteroaromatic ring systems having 5 to 40 aromaticring atoms, which may in each case be substituted by one or moreradicals R⁵, where two adjacent substituents R⁰ may form a mono- orpolycyclic, aliphatic ring system or aromatic ring system, which may besubstituted by one or more radicals R⁵.
 12. Compound according to claim1, wherein the group E is, identically or differently, on eachoccurrence, selected from —C(R^(E))₂—, —Si(R^(E))₂—, and the group offormula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1) or (G-2) and where E⁰ and R⁴ have the same meaning asin claim
 1. 13. Compound according to claim 1, wherein n is equal to 1and the group G is selected from the groups of formulae (G-1-1) to(G-1-23),

where the dashed bonds indicate the bonding to the adjacent groups asdepicted in formula (1); the groups of formulae (G-1-1) to (G-1-23) maybe substituted by one or more radicals R⁴ or one or more groups Ar^(L)at any free positions; E² stands, on each occurrence, identically ordifferently, for —C(R^(E))₂—, —O— or —S—; and the symbols E, R^(E) havethe same meaning as in claim
 1. 14. Compound according to claim 1,wherein n is equal to 0 and the group G is selected from the groups offormulae (G-2-1) to (G-2-40),

where the dashed bond indicates the bonding to the adjacent groups asdepicted in formula (1); the groups of formulae (G-2-1) to (G-2-40) maybe substituted by one or more radicals R⁴ or Ar^(L) at any freepositions; E² stands, on each occurrence, identically or differently,for —C(R^(E))₂—, —O— or —S—; and the symbols E and R^(E) have the samemeaning as in claim
 1. 15. Formulation comprising at least one compoundaccording to claim 1 and at least one solvent.
 16. Electronic devicecomprising at least one compound according to claim 1, selected from thegroup consisting of organic electroluminescent devices, organicintegrated circuits, organic field-effect transistors, organic thin-filmtransistors, organic light-emitting transistors, organic solar cells,dye-sensitised organic solar cells, organic optical detectors, organicphotoreceptors, organic field-quench devices, light-emittingelectrochemical cells, organic laser diodes and organic plasmon emittingdevices.
 17. Electronic device according to claim 16, which is anorganic electroluminescent device, wherein the compound according toclaim 1 is a fluorescent emitter or a matrix material for fluorescentemitters.
 18. Compound according to claim 11, wherein R⁰ stands on eachoccurrence, identically or differently, for a straight-chain alkylhaving 1 to 10 C atoms or a cyclic alkyl group having 3 to 10 C atoms.19. Compound of the formulae (2) to (10),

where the following applies to the symbols and indices used: Ar¹, Ar²,Ar³, Ar⁴ stand on each occurrence, identically or differently, for: anaromatic or heteroaromatic ring system having 5 to 60 aromatic ringatoms, which may in each case be substituted by one or more radicals R¹;or a group Ar^(L); Ar^(L) stands on each occurrence, identically ordifferently, for a group of formula (ArL-1),

where the dashed bond in formula (ArL-1) indicates the bonding to thestructure of formula (1); X stands for CR² or X stands for C, if it isbonded to Ar⁵, Ar⁶, R³ or to an adjacent fluorene-type derivative unit;Y stands on each occurrence, identically or differently, for —BR⁰—,—C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —C(R⁰)₂—O—, —C(R⁰)₂—S—, —R⁰C═CR⁰—, —R⁰C═N—,—Si(R⁰)₂—, —Si(R⁰)₂—Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—, —C(═C(R⁰)₂)—, —O—,—S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and —P((═O)R⁰)—; Ar⁵, Ar⁶ stand oneach occurrence, identically or differently, for an aryl or heteroarylgroup having 6 to 18 aromatic ring atoms, which may in each case besubstituted by one or more radicals R³; G is, when n is 1, a group offormula (G-1),

where the dashed bonds indicate the bonding to the group —NAr³Ar⁴ and—NAr¹Ar²; G is, when n is 0, a group of formula (G-2),

where the dashed bond indicates the bonding to the group —NAr³Ar⁴; Ar⁷stands on each occurrence, identically or differently, for an aryl orheteroaryl group having 6 to 18 aromatic ring atoms, which may in eachcase be substituted by one or more radicals R⁴, wherein at least one ofthe group Ar⁷ in formulae (G-1) and (G-2) has 10 or more aromatic ringatoms; Ar⁸ stands on each occurrence, identically or differently, for anaryl or heteroaryl group having 6 to 18 aromatic ring atoms, which mayin each case be substituted by one or more radicals R⁴ or one or moregroups Ar^(L); E is identically or differently on each occurrence,selected from —BR^(E)—, —C(R^(E))₂—, —C(R^(E))₂—C(R^(E))₂—,—C(R^(E))₂—O—, —C(R^(E))₂—S—, —R^(E)C═CR^(E)—, —R^(E)C═N—, Si(R^(E))₂,—Si(R^(E))₂—Si(R^(E))₂—, —C(═O)—, —C(═NR^(E))—, —C(═C(R^(E))₂)—, —O—,—S—, —S(═O)—, —SO₂—, —N(R^(E))—, —P(R^(E))— and —P((═O)R^(E))—; or E isa group of formula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1) or (G-2); and where two groups E may be in a cis- ortrans-position relative to each other; E⁰ is identically or differentlyon each occurrence, selected from the group consisting of a single bond,—BR⁴—, —C(R⁴)₂—, —C(R⁴)₂—C(R⁴)₂—, —C(R⁴)₂—O—, —C(R⁴)₂—S—, —R⁴C═CR⁴—,—R⁴C═N—, Si(R⁴)₂, —Si(R⁴)₂—Si(R⁴)₂—, —C(═O)—, —C(═NR⁴)—, —C(═C(R⁴)₂)—,—O—, —S—, —S(═O)—, —SO₂—, —N(R⁴)—, —P(R⁴)— and —P((═O)R⁴)—; R^(E) standson each occurrence, identically or differently, for: H, D, F, Cl, Br, I,a straight-chain alkyl having 1 to 40 C atoms or branched or a cyclicalkyl group having 3 to 40 C atoms, each of which may be substituted byone or more radicals R⁵, where in each case one or more non-adjacent CH₂groups may be replaced by R⁵C═CR⁵, C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O,C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, S or CONR⁵ and where one or more Hatoms may be replaced by D, F, Cl, Br, I or CN, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁵, where twoadjacent substituents R^(E) may form a mono- or polycyclic, aliphaticring system or aromatic ring system, which may be substituted by one ormore radicals R⁵; or R^(E) stands for a group Ar^(L); R⁰, R¹, R², R³, R⁴stand on each occurrence, identically or differently, for: a groupselected from H, D, F, Cl, Br, I, CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂,S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁵)₃, B(OR⁵)₂, OSO₂R⁵, a straight-chainalkyl, alkoxy or thioalkyl groups having 1 to 40 C atoms or branched ora cyclic alkyl, alkoxy or thioalkyl groups having 3 to 40 C atoms, eachof which may be substituted by one or more radicals R⁵, where in eachcase one or more non-adjacent CH₂ groups may be replaced by R⁵C═CR⁵,C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O, C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, Sor CONR⁵ and where one or more H atoms may be replaced by D, F, Cl, Br,I, CN or NO₂, an aromatic or heteroaromatic ring systems having 5 to 60aromatic ring atoms, which may in each case be substituted by one ormore radicals R⁵, or an aryloxy groups having 5 to 40 aromatic ringatoms, which may be substituted by one or more radicals R⁵; or R⁰, R¹,R², R³ and/or R⁴ stands for a group Ar^(L); where two adjacentsubstituents R⁰, two adjacent substituents R¹, two adjacent substituentsR², two adjacent substituents R³ and/or two adjacent substituents R⁴,may form a mono- or polycyclic, aliphatic ring system or aromatic ringsystem, which may be substituted by one or more radicals R⁵; wherein thecompound of formulae (2) to (5) bears at least one group R⁰, R¹, R², R³,R⁴ or R^(E), which stands for a straight-chain alkyl group having 1 to40 C atoms or a branched or a cyclic alkyl group having 3 to 40 C atoms,each of which may be substituted by one or more radicals R⁶ R⁵ stands oneach occurrence, identically or differently, for H, D, F, Cl, Br, I,CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂, S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁶)₃,B(OR⁶)₂, OSO₂R⁶, a straight-chain alkyl, alkoxy or thioalkyl groupshaving 1 to 40 C atoms or branched or cyclic alkyl, alkoxy or thioalkylgroups having 3 to 40 C atoms, each of which may be substituted by oneor more radicals R⁶, where in each case one or more non-adjacent CH₂groups may be replaced by R⁶C═CR⁶, C≡C, Si(R⁶)₂, Ge(R⁶)₂, Sn(R⁶)₂, C═O,C═S, C═Se, P(═O)(R⁶), SO, SO₂, O, S or CONR⁶ and where one or more Hatoms may be replaced by D, F, Cl, Br, I, CN or NO₂, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁶, or anaryloxy group having 5 to 60 aromatic ring atoms, which may besubstituted by one or more radicals R⁶, where two adjacent substituentsR⁵ may form a mono- or polycyclic, aliphatic ring system or aromaticring system, which may be substituted by one or more radicals R⁶; Ar isan aromatic or heteroaromatic ring system having 5 to 24 aromatic ringatoms, which may in each case also be substituted by one or moreradicals R⁶; R⁶ stands on each occurrence, identically or differently,for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkylgroups having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy orthioalkyl groups having 3 to 20 C atoms, where in each case one or morenon-adjacent CH₂ groups may be replaced by SO, SO₂, O, S and where oneor more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic orheteroaromatic ring system having 5 to 24 C atoms; n is equal to 0 or 1;i is equal to 0, 1 or 2; q, r are on each occurrence, identically ordifferently, an integer selected from 1 to 10; p, s, t are on eachoccurrence, identically or differently, an integer selected from 0 to10; and where the compounds of formula (1) comprise at least one groupAr¹, Ar², Ar³, Ar⁴, R^(E), R⁰, R¹, R², R³ or R⁴, which stands for agroup Ar^(L).
 20. Compound of the formulae (2) to (10),

where the following applies to the symbols and indices used: Ar¹, Ar²,Ar³, Ar⁴ stand on each occurrence, identically or differently, for: anaromatic or heteroaromatic ring system having 5 to 60 aromatic ringatoms, which may in each case be substituted by one or more radicals R¹;or a group Ar^(L); Ar^(L) stands on each occurrence, identically ordifferently, for a group of formula (ArL-1),

where the dashed bond in formula (ArL-1) indicates the bonding to thestructure of formula (1); X stands for CR² or X stands for C, if it isbonded to Ar⁵, Ar⁶, R³ or to an adjacent fluorene-type derivative unit;Y stands on each occurrence, identically or differently, for —BR⁰—,—C(R⁰)₂—, —C(R⁰)₂—C(R⁰)₂—, —C(R⁰)₂—O—, —C(R⁰)₂—S—, —R⁰C═CR⁰—, —R⁰C═N—,—Si(R⁰)₂—, —Si(R⁰)₂—Si(R⁰)₂—, —C(═O)—, —C(═NR⁰)—, —C(═C(R⁰)₂)—, —O—,—S—, —S(═O)—, —SO₂—, —N(R⁰)—, —P(R⁰)— and —P((═O)R⁰)—; Ar⁵ stand on eachoccurrence, identically or differently, for an aryl or heteroaryl grouphaving 6 to 18 aromatic ring atoms, which may in each case besubstituted by one or more radicals R³; Ar⁶ stand on each occurrence,identically or differently, for an aryl group having 6 to 14 aromaticring atoms, which may in each case be substituted by one or moreradicals R³; G is, when n is 1, a group of formula (G-1),

where the dashed bonds indicate the bonding to the group —NAr³Ar⁴ and—NAr¹Ar²; G is, when n is 0, a group of formula (G-2),

where the dashed bond indicates the bonding to the group —NAr³Ar⁴; Ar⁷stands on each occurrence, identically or differently, for an aryl orheteroaryl group having 6 to 18 aromatic ring atoms, which may in eachcase be substituted by one or more radicals R⁴, wherein at least one ofthe group Ar⁷ in formulae (G-1) and (G-2) has 10 or more aromatic ringatoms; Ar⁸ stands on each occurrence, identically or differently, for anaryl or heteroaryl group having 6 to 18 aromatic ring atoms, which mayin each case be substituted by one or more radicals R⁴ or one or moregroups Ar^(L); E is identically or differently on each occurrence,selected from —C(R^(E))₂—, or a group of formula (E-1),

where the symbol * in formula (E-1) indicates the corresponding group Ein formula (G-1) or (G-2); and where two groups E may be in a cis- ortrans-position relative to each other; E⁰ is identically or differentlyon each occurrence, selected from the group consisting of a single bond,—BR⁴—, —C(R⁴)₂—, —C(R⁴)₂—C(R⁴)₂—, —C(R⁴)₂—O—, —C(R⁴)₂—S—, —R⁴C═CR⁴—,—R⁴C═N—, Si(R⁴)₂, —Si(R⁴)₂—Si(R⁴)₂—, —C(═O)—, —C(═NR⁴)—, —C(═C(R⁴)₂)—,—O—, —S—, —S(═O)—, —SO₂—, —N(R⁴)—, —P(R⁴)— and —P((═O)R⁴)—; R^(E) standson each occurrence, identically or differently, for: H, D, F, Cl, Br, I,a straight-chain alkyl having 1 to 40 C atoms or branched or a cyclicalkyl group having 3 to 40 C atoms, each of which may be substituted byone or more radicals R⁵, where in each case one or more non-adjacent CH₂groups may be replaced by R⁵C═CR⁵, C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O,C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, S or CONR⁵ and where one or more Hatoms may be replaced by D, F, Cl, Br, I or CN, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁵, where twoadjacent substituents R^(E) may form a mono- or polycyclic, aliphaticring system or aromatic ring system, which may be substituted by one ormore radicals R⁵; or R^(E) stands for a group Ar^(L); R⁰, R¹, R², R³, R⁴stand on each occurrence, identically or differently, for: a groupselected from H, D, F, Cl, Br, I, CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂,S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁵)₃, B(OR⁵)₂, OSO₂R⁵, a straight-chainalkyl, alkoxy or thioalkyl groups having 1 to 40 C atoms or branched ora cyclic alkyl, alkoxy or thioalkyl groups having 3 to 40 C atoms, eachof which may be substituted by one or more radicals R⁵, where in eachcase one or more non-adjacent CH₂ groups may be replaced by R⁵C═CR⁵,C≡C, Si(R⁵)₂, Ge(R⁵)₂, Sn(R⁵)₂, C═O, C═S, C═Se, P(═O)(R⁵), SO, SO₂, O, Sor CONR⁵ and where one or more H atoms may be replaced by D, F, Cl, Br,I, CN or NO₂, an aromatic or heteroaromatic ring systems having 5 to 60aromatic ring atoms, which may in each case be substituted by one ormore radicals R⁵, or an aryloxy groups having 5 to 40 aromatic ringatoms, which may be substituted by one or more radicals R⁵; or R⁰, R¹,R², R³ and/or R⁴ stands for a group Ar^(L); where two adjacentsubstituents R⁰, two adjacent substituents R¹, two adjacent substituentsR², two adjacent substituents R³ and/or two adjacent substituents R⁴,may form a mono- or polycyclic, aliphatic ring system or aromatic ringsystem, which may be substituted by one or more radicals R⁵; wherein thecompound of formulae (2) to (5) bears at least one group R⁰, R¹, R², R³,R⁴ or R^(E), which stands for a straight-chain alkyl group having 1 to40 C atoms or a branched or a cyclic alkyl group having 3 to 40 C atoms,each of which may be substituted by one or more radicals R⁶ R⁵ stands oneach occurrence, identically or differently, for H, D, F, Cl, Br, I,CHO, CN, N(Ar)₂, C(═O)Ar, P(═O)(Ar)₂, S(═O)Ar, S(═O)₂Ar, NO₂, Si(R⁶)₃,B(OR⁶)₂, OSO₂R⁶, a straight-chain alkyl, alkoxy or thioalkyl groupshaving 1 to 40 C atoms or branched or cyclic alkyl, alkoxy or thioalkylgroups having 3 to 40 C atoms, each of which may be substituted by oneor more radicals R⁶, where in each case one or more non-adjacent CH₂groups may be replaced by R⁶C═CR⁶, C≡C, Si(R⁶)₂, Ge(R⁶)₂, Sn(R⁶)₂, C═O,C═S, C═Se, P(═O)(R⁶), SO, SO₂, O, S or CONR⁶ and where one or more Hatoms may be replaced by D, F, Cl, Br, I, CN or NO₂, an aromatic orheteroaromatic ring systems having 5 to 60 aromatic ring atoms, whichmay in each case be substituted by one or more radicals R⁶, or anaryloxy group having 5 to 60 aromatic ring atoms, which may besubstituted by one or more radicals R⁶, where two adjacent substituentsR⁵ may form a mono- or polycyclic, aliphatic ring system or aromaticring system, which may be substituted by one or more radicals R⁶; Ar isan aromatic or heteroaromatic ring system having 5 to 24 aromatic ringatoms, which may in each case also be substituted by one or moreradicals R⁶; R⁶ stands on each occurrence, identically or differently,for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkylgroups having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy orthioalkyl groups having 3 to 20 C atoms, where in each case one or morenon-adjacent CH₂ groups may be replaced by SO, SO₂, O, S and where oneor more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic orheteroaromatic ring system having 5 to 24 C atoms; n is equal to 0 or 1;i is equal to 0, 1 or 2; q, r are on each occurrence, identically ordifferently, an integer selected from 1 to 10; p, s, t are on eachoccurrence, identically or differently, an integer selected from 0 to10; and where the compounds of formula (1) comprise at least one groupAr¹, Ar², Ar³, Ar⁴, R^(E), R⁰, R¹, R², R³ or R⁴, which stands for agroup Ar^(L).